dmaengine: pxa: fix double counting of the hw descriptors
pxad_alloc_desc() was converted from
kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc), GFP_NOWAIT)
to kzalloc_flex(), which sets the __counted_by() counter sw_desc->nb_desc
itself - but only where the compiler has __builtin_counted_by_ref(), so
from gcc 15.1 or clang 22.1 on. The loop below it still increments
nb_desc, which makes it come out doubled there and correct elsewhere.
nb_desc is what pxad_free_desc() iterates over and what
set_updater_desc() indexes from, so set it explicitly and drop the
increment. The error path has to lower it to the number of descriptors
allocated so far, otherwise pxad_free_desc() would free entries that were
never allocated.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
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| Linux | Linux | affected |
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No data.
No data.
No data available yet.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Tue, 06 Oct 2026 09:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: dmaengine: pxa: fix double counting of the hw descriptors pxad_alloc_desc() was converted from kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc), GFP_NOWAIT) to kzalloc_flex(), which sets the __counted_by() counter sw_desc->nb_desc itself - but only where the compiler has __builtin_counted_by_ref(), so from gcc 15.1 or clang 22.1 on. The loop below it still increments nb_desc, which makes it come out doubled there and correct elsewhere. nb_desc is what pxad_free_desc() iterates over and what set_updater_desc() indexes from, so set it explicitly and drop the increment. The error path has to lower it to the number of descriptors allocated so far, otherwise pxad_free_desc() would free entries that were never allocated. | |
| Title | dmaengine: pxa: fix double counting of the hw descriptors | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-06T08:46:17.919Z
Reserved: 2026-09-25T10:25:14.340Z
Link: CVE-2026-98324
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-06T09:18:24.573
Modified: 2026-10-06T09:18:24.573
Link: CVE-2026-98324
Redhat
No data.
OpenCVE Enrichment
No data.
No weakness.